Retarder for boiler-tubes.



D E. ERICKSON.

RETARDER FOR BOLER TUBES.

APPLICATION FILED JUNE 17. I914.

1,156,281. Patented 001. 12, 1915.

INVENTOR, Daniel E. Eric/(son M $605K ATTORNEY WITNESSES COLUMBIA PLANODRAPH co., WASHINGTON, D. c.

UNITED STATES PATENT GFFICE.

DANIEL E. ERICKSON, OF BERKELEY, CALIFORNIA, ASSIGNOR TO ROBERT S. MOORE, OF SAN FRANCISCO, CALIFORNIA.

RETARDER FOR BOILER-TUBES.

To all whom it may concern Be it known that I, DANIEL E. EmonsoN, a citizen of the United States, residing at Berkeley, in the county of Alameda and State of California, have invented new and useful Improvements in Retarders for Boiler-Tubes, of which the following is a specification.

The present invention relates to improve ments in retarders for fire tube boilers.

The retarders at present generally in use for this purpose are twisted or helical iiat bars which are inserted in the tubes of the boiler and extend through a considerable part of the length of said tubes. The objections to this form of retarder are that a great amount of metal is required, that the retarders when removed from the boiler, as for the purpose of cleaning the tubes, occupy a great deal of valuable space, and that they cannot be readily adjusted to retard the products of combustion in the tubes to give the best result.

The object of the present invention is to provide a retarder for a boiler tube which Will be of light weight and small cost, which will occupy but little space when removed from the boiler tube, and which can readily be adjusted in position so as to give the best results in retardation of the hot gases.

In the accompanying drawing, Figure 1 is a vertical section of a fire tube boiler equipped with my invention; Fig. 2 is an enlarged sectional view of an end of the fire tubes having the invention applied thereto; Fig. 3 is a perspective View of a retarder detached.

Referring to the drawing, 1 indicates a fire tube of a boiler and 2 a head of the boiler to which one end of said tube is attached.

3 indicates my improved retarder, and it consists of a single piece of sheet metal having a substantially square central portion 4, formed with a circular central hole 5, and, extending from opposite sides of said central portion, in planes parallel with each other and at right angles to the plane of the central portion, narrow necks 6, terminating in comparatively wide and long terminal portions 7 of which the central portions 8 are approximately cylindrical about an axis through the center of the circular hole, said central portions flaring into approximately plane marginal portions 9. By reason of Patented Oct. 12, 1915.

Serial No. 845,630.

the narrowness of the necks 6, the extensions 7 can be sprung inward toward each other, so as to be capable of being easily inserted in an end of the tube 1 of the boiler, and, when pressure is removed from said extensions, they spring out from each other and engage the inner surface of the tube, and hold the retarder in the position in which it has been inserted. By sufficient force applied thereto, however, the retarder can be pushed into or drawn out from the tube as desired. hen completely pushed into the tube, the square central portion a abuts against the end of the tube, and the hot gases escape only through the central hole 5, and the retarder then produces its maximum effect of retardation. When drawn out from said tube, however, the hot gases can fiow not only through the central hole 5, but also between the end of the tube and the square central portion and around the edges of the latter, and it is evident that the farther the retarder is drawn out from the tube, the wider is the space through which the hot gases can flow. Thus by properly adjusting the retarders in the tubes any desired de gree of retardation can be effected. It is, however, very important in practice that it should not be left to the discretion of the firemen or other mechanics employed on the boiler to adjust the position of the retarders therein. The peculiar form of my improved retarder permits of this being readily taken care of. For to effect this result it is only necessary, after the retarder has been once adjusted in the end of the tube at the proper position, to hammer down one corner 10, or two opposite corners, of the square central portion so that said corner 01' corners is or are in contact with the face of the boiler tube, thus limiting the extent to which the retarder can be inserted in the boiler tube. The firemen or other mechanics employed in cleaning the boiler or otherwise thereon, in replacing the retarders in the boiler tubes, need only take care that they are pushed into said tubes as far as possible, the inwardly bent corners 10 of the central portion, abutting against the end of the boiler plate, arresting the retarders at the proper position to give the result desired.

I claim A retarder for boiler tubes consisting of a piece of spring sheet metal having a centrally apertured central portion, narrow necks extending at right angles from said central portion and enlarged extensions adapted to be retained by spring pressure in the interior of the tube, said central portion having parts adapted to be bent back to abut against the end of the tube or boiler sheet to limit the inward movement of the retarder in the tube.

In testimony whereof I have hereunto set my hand in the presence of two subscrlbing Witnesses.

DANIEL E. ERICKSON.

itnesses FRANCIS M. VRIGHT, D. B. Rrcrmnns.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. G. 

